xref: /openbmc/linux/tools/lib/perf/threadmap.c (revision dc6a81c3)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <perf/threadmap.h>
3 #include <stdlib.h>
4 #include <linux/refcount.h>
5 #include <internal/threadmap.h>
6 #include <string.h>
7 #include <asm/bug.h>
8 #include <stdio.h>
9 
10 static void perf_thread_map__reset(struct perf_thread_map *map, int start, int nr)
11 {
12 	size_t size = (nr - start) * sizeof(map->map[0]);
13 
14 	memset(&map->map[start], 0, size);
15 	map->err_thread = -1;
16 }
17 
18 struct perf_thread_map *perf_thread_map__realloc(struct perf_thread_map *map, int nr)
19 {
20 	size_t size = sizeof(*map) + sizeof(map->map[0]) * nr;
21 	int start = map ? map->nr : 0;
22 
23 	map = realloc(map, size);
24 	/*
25 	 * We only realloc to add more items, let's reset new items.
26 	 */
27 	if (map)
28 		perf_thread_map__reset(map, start, nr);
29 
30 	return map;
31 }
32 
33 #define thread_map__alloc(__nr) perf_thread_map__realloc(NULL, __nr)
34 
35 void perf_thread_map__set_pid(struct perf_thread_map *map, int thread, pid_t pid)
36 {
37 	map->map[thread].pid = pid;
38 }
39 
40 char *perf_thread_map__comm(struct perf_thread_map *map, int thread)
41 {
42 	return map->map[thread].comm;
43 }
44 
45 struct perf_thread_map *perf_thread_map__new_dummy(void)
46 {
47 	struct perf_thread_map *threads = thread_map__alloc(1);
48 
49 	if (threads != NULL) {
50 		perf_thread_map__set_pid(threads, 0, -1);
51 		threads->nr = 1;
52 		refcount_set(&threads->refcnt, 1);
53 	}
54 	return threads;
55 }
56 
57 static void perf_thread_map__delete(struct perf_thread_map *threads)
58 {
59 	if (threads) {
60 		int i;
61 
62 		WARN_ONCE(refcount_read(&threads->refcnt) != 0,
63 			  "thread map refcnt unbalanced\n");
64 		for (i = 0; i < threads->nr; i++)
65 			free(perf_thread_map__comm(threads, i));
66 		free(threads);
67 	}
68 }
69 
70 struct perf_thread_map *perf_thread_map__get(struct perf_thread_map *map)
71 {
72 	if (map)
73 		refcount_inc(&map->refcnt);
74 	return map;
75 }
76 
77 void perf_thread_map__put(struct perf_thread_map *map)
78 {
79 	if (map && refcount_dec_and_test(&map->refcnt))
80 		perf_thread_map__delete(map);
81 }
82 
83 int perf_thread_map__nr(struct perf_thread_map *threads)
84 {
85 	return threads ? threads->nr : 1;
86 }
87 
88 pid_t perf_thread_map__pid(struct perf_thread_map *map, int thread)
89 {
90 	return map->map[thread].pid;
91 }
92